How to get Spring Session for GemFire session information by function execution service via gfsh

Products

• VMware Tanzu Gemfire

Issue/Introduction

This article describes  how to log Spring Session for VMware Tanzu GemFire session information by function execution service using gfsh.

Environment

Product Version: 9.10

Resolution

Step1:
Create a on-region function execution service class like the below.

import org.apache.geode.cache.Declarable;
import org.apache.geode.cache.execute.Function;
import org.apache.geode.cache.execute.FunctionContext;
import org.apache.geode.cache.execute.RegionFunctionContext;
import org.apache.geode.cache.partition.PartitionRegionHelper;
import org.apache.geode.cache.Region;
import java.util.*;
import static org.springframework.session.data.gemfire.AbstractGemFireOperationsSessionRepository.GemFireSession;

public class DumpSessionsFunction implements Function, Declarable {

    public void execute(FunctionContext context) {
        RegionFunctionContext rfc = (RegionFunctionContext) context;
        Region region = PartitionRegionHelper.getLocalDataForContext(rfc);
        String sessions = getSessions(region);
        context.getCache().getLogger().info(sessions);
        context.getResultSender().lastResult(true);
    }
 

    private String getSessions(Region region) {
        Set keySet = region.entrySet();
        String header = "This member contains the following " + keySet.size() + " primary sessions: " + "\n";
        
        StringBuffer str = new StringBuffer();

        Iterator iterator = keySet.iterator();
        while (iterator.hasNext()) {
            Region.Entry e = (Region.Entry) iterator.next();
            str.append("Session Key: " + e.getKey() + "\n");
            str.append("Session Value: "+ e.getValue() + "\n\n");
        }

		return header + str.toString();

    }

    public String getId() {
        return getClass().getSimpleName();
    }

    public boolean optimizeForWrite() {
        return true;
    }

    public static int sizeObject(Object o) {
		return ReflectionObjectSizer.getInstance().sizeof(o);
	}

}

Step2:
Compile this function code and create a jar, deploy it into Gemfire Cluster.
For example:

user1$ javac DumpSessionsFunction.java
user1$ jar cf DumpSessionsFunction.jar DumpSessionsFunction.class

gfsh>deploy --jar=/Users/user1/DumpSessionsFunction/DumpSessionsFunction.jar

Deploying files: DumpSessionsFunction.jar
Total file size is: 0.00MB

Continue?  (Y/n): Y
   Member    |       Deployed JAR       | Deployed JAR Location
------------ | ------------------------ | -----------------------------------------------------------------------------------
cacheserver1 | DumpSessionsFunction.jar | /Users/user1/cacheserver1/DumpSessionsFunction.v1.jar
cacheserver2 | DumpSessionsFunction.jar | /Users/user1/cacheserver2/DumpSessionsFunction.v1.jar
cacheserver3 | DumpSessionsFunction.jar | /Users/user1/cacheserver3/DumpSessionsFunction.v1.jar
cacheserver4 | DumpSessionsFunction.jar | /Users/user1/cacheserver4/DumpSessionsFunction.v1.jar

Step3:
This function is an on-region function and should be executed as the following:

execute function --id=DumpSessionsFunction --region=/SpringSessionRegionName

For example:

gfsh>execute function --id=DumpSessionsFunction --region=/SpringSessionRegion1
   Member    | Status | Message
------------ | ------ | ------------------------
cacheserver1 | OK     | [true, true, true, true]

Step4:
You can confirm the session information from cacheservers's log.
For example:

gfsh>show log --member=cacheserver1
[info 2022/01/05 19:26:59.794 JST cacheserver1 <Function Execution Processor3> tid=0xac] This member contains the following 3 primary sessions: 
Session Key: 856c246c-c985-423c-8798-4c23408fdc2a
Session Value: { @type = org.springframework.session.data.gemfire.AbstractGemFireOperationsSessionRepository$GemFireSession, id = 856c246c-c985-423c-8798-4c23408fdc2a, creationTime = 2022-01-05T10:26:46.592Z, lastAccessedTime = 2022-01-05T10:26:46.592Z, maxInactiveInterval = PT15M, principalName = null }

Session Key: f42d3fc7-33eb-47d6-9dea-dd344dcb923d
Session Value: { @type = org.springframework.session.data.gemfire.AbstractGemFireOperationsSessionRepository$GemFireSession, id = f42d3fc7-33eb-47d6-9dea-dd344dcb923d, creationTime = 2022-01-05T10:21:32.305Z, lastAccessedTime = 2022-01-05T10:21:32.305Z, maxInactiveInterval = PT15M, principalName = null }

Session Key: 6ece35a5-32d1-4d9e-9a00-ac32d1e56fee
Session Value: null